Jesus is our soap-like Savior. He was not afraid to touch this ritually unclean leper, making himself unclean according to the law. Instead of contagious skin disease or uncleanness being communicated to Jesus, Jesus communicated contagious holiness to the leper.
A friend of mine recently listened to that message and sent the following insightful and encouraging expansion of the word picture (thanks, Jeff!):
In your sermon, Jesus was soap-like particularly in His divine ability to cleanse without Himself getting dirty--i.e., the mechanism of cleansing is unidirectional, from soap to dirty hands, from Savior to poor and needy sinner. Jesus is also soap-like in His incarnation: without soap, you can't get oils off of your hands with just water. The oil and water won't mix, the water will run off your hands, and the oil will remain behind. Soap is effective because at its molecular level, it bridges the gap between oil and water, uniting them molecularly: soap has a polar hydrophilic end (water-loving) and a non-polar lipophilic end (fat-loving). Soap unites oil and water molecularly, because it is uniquely equipped to bond with both of them. So, in a sense, soap is able to "reconcile" water and oil, allowing one to clean off the other...the parallels between a loving God, His messy creation, and the soap-like Savior, are rich indeed.2 Corinthians 5:21
For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God.Hebrews 2:14-18 (emphasis added)
Since therefore the children share in flesh and blood, he himself likewise partook of the same things, that through death he might destroy the one who has the power of death, that is, the devil, and deliver all those who through fear of death were subject to lifelong slavery. For surely it is not angels that he helps, but he helps the offspring of Abraham. Therefore he had to be made like his brothers in every respect, so that he might become a merciful and faithful high priest in the service of God, to make propitiation for the sins of the people. For because he himself has suffered when tempted, he is able to help those who are being tempted.